Most off color references are to comic relief that is of the dark variety. But this is no joke and the off color water I’m referring to is technically known as “gray water.” So gray water is somewhere between “white water” and “black water.” White being potable or drinkable water and black being considered sewage i.e. containing human waste which is sent to sewage treatment facilities for clean up before it is returned to the environment.

The thing is that appropriate gray water can be recycled and used for other purposes like landscape irrigation or in our case for use in flushing toilets and urinals after which the water is sent to the municipal sanitary sewer system for treatment. This is yet another way to conserve precious potable water and is also gaining the Visitor Center project LEED points. Once again, several points are in the balance for sustainable design.

LEED Credit 2 Innovative Wastewater Technologies / 1 Point

Reduce potable water use for building sewage conveyance through the use of recycled gray water and on-site treated wastewater.

LEED Credit 3; 3.1 Water use Reduction up to 20% and 3.2 up to 30% / 1 Point each; if we achieve 45% we get another point for “innovation in design.”

Maximize water efficiency within buildings to reduce the burden on municipal water supply and waste water systems. Consider reuse of gray water for non-potable applications such as toilet and urinal flushing.

We will be collecting waste water from sinks, lavatories and a shower that are located in the Visitor Center. These are sent to an on-site treatment system, the water is stored in a tank and then pumped to the toilets and urinals for flushing. There are several pieces and parts to the design of this overall system. The design and placement of all the components was a multidisciplinary team effort along with incorporating the details in the construction documents.

I’ll share the approach to the design and solution with you next post.